1. Field of the Invention
The present invention relates to a sheet transporting apparatus, and more specifically, a sheet transporting apparatus which has a function of transporting sheets ejected from an image forming apparatus such as a copying machine, a laser printer, etc. to a sheet storing unit and feeding back the sheets to the image forming apparatus, and a function of transporting sheets ejected from the image forming apparatus to a sheet handling apparatus attached downstream thereof.
2. Description of Related Art
Recently, many kinds of apparatuses wherein sheets ejected from an image forming apparatus with an image on one side are stored and then fed back to the image forming apparatus, have been proposed and developed to make a duplex/composite copying operation available. Further, in many cases, a sheet handling apparatus such as a sorter, a finisher with a stapling function, etc. is attached downstream of the storing/refeeding apparatus. However, a large space is necessary to place these apparatuses connecting each other, and accordingly each of the apparatuses is desired to be made into a compact type. Especially, in an apparatus wherein both a duplex and a composite copying operations are available, a mechanism for turning over sheets is necessary, so that the apparatus becomes larger because of the mechanism.
Conventionally, there have been used a type of apparatus comprising two paths for leading sheets to respective entrances, which are facing each other, of a sheet storing unit, which are used in a duplex copying mode and in a composite copying mode respectively. However, the arrangement makes the apparatus larger because of the elongated paths and a mechanism for treating a sheet jam complicated. Also, a switchback method that sheets are transported selectively forward and backward by a pair of rollers which can be driven normally and reversely has been adopted. The switchback method helps in making the apparatus compact because a path is used in both a duplex and a composite mode, and the treatment of a sheet ]am becomes simple. However, as diverting means and the rollers which can be driven normally and reversely are installed in a sorter conventionally, the advantage of the compact apparatus has not been made good use of, and the apparatus does not apparatuses is desired to be made into a compact type. function as a sheet transporting apparatus for a duplex/composite copying operation without the sorter.